J. Gresham Machen is best known for his battle against theological liberalism in the northern Presbyterian church in the US (the PCUSA), first founding a seminary (in 1929) and then an independent missions agency in 1933.
This latter action in particular was swiftly condemned by his denomination, and after a couple years of trials and appeals, he was defrocked in 1936. Not long after, he founded a new denomination – the Orthodox Presbyterian Church.
I'd like to know if it's documented anywhere that Machen seriously considered joining another Presbyterian body in the US prior to creating the OPC. At the time, there weren't nearly as many Presbyterian options, but others did exist, such as the PCUS (in the South), the ARP, and the RPCNA.
Do we have any evidence, particularly from his writings, that Machen considered joining another Presbyterian denomination instead of founding a new one?